Filtrability recorder



June 10, 1952 P. BOUCHER ET AL FILTRABILITY RECORDER 2 SHEETS-SHEET 1 F I'G. 2

Filed Aug. 13, 1949 a. SUM s Rad mwN/Mw www ww .IFM T mii A /f June 10, 1952 P. BOUCHER ET AL 2,599,742

FILTRABILITY RECORDER Filed Allg. 15, 1949 2 SHEETS-@SHEET 2 FIG. 3

.lill

AOR

Patented June 10, 1952 FILTRABILITY RECORDER Percival Lionel Boucher, Kilmarnock, Scotland,

and Norman Andrew Forster Rowntree, Hartford, near Northwich, England, assignors to Glenfield & Kennedy Limited, Kilmarnock,

Ayrshire,

Scotland, a corporation of Great Britain and Northern Ireland Application August 13, 1949, Serial No. 110,104

, 3 Claims. l

The subject of this invention is a filtrability recorder for measuring the property of a fluid referred to as its filtrability as defined in the specification of our co-pending application Serial No. 676,084, now Patent No. 2,572,436.

For the purpose of what follows, the filtrahility of a fluid is taken as a mathematical function of lthe rate of increase of the loss of head with respect to the volume filtered at constant rate of flow when flowing through a particular filter.

A filtrabilityA recorder according to the invention comprises a tank having a drain opening and containing an inner vessel having an open top, an outlet pipe leading from the inner vessel to the inlet of a filtering unit, a flow con-- troller or module connected to the outlet of the filtering unit, a pressure recorder connected to the outlet of the filtering unit through the intermediary of valve means, the outlet of the filtering unit being connectible to a source of supply of cleaningfluid through the intermediary of second valve means, anda time cycle controller adapted to operate the valve means at predetermined intervals.

The pressure recorder may be a known type of strip chart or other recorder with means for automatic pen adjustment through a bellows mechanism adapted to record the instantaneous value of the pressure at the outlet of the filtering unit.

The filtering unit may be of any known type. The flow controller or module is of known type and may consist essentially of a piston-operated needle valve, the piston operating in a cylinder having a vertical axis, the submerged weight of the piston with its attached needle being balanced by the differential pressure set up by the fiow between the piston and the cylinder and through an adjustable by-pass in hydraulic parallel with the piston clearance.

The two valves may be solenoid-actuated stop valves of known type.

The time cycle controller may include an electric clock adapted to operate mercury switches electrically connected to the solenoids.

A practical embodiment of the Ainvention is illustrated in the accompanying drawings in which Fig. l is a View looking on the front of a recorder installation, Fig. 2 is a section through 2-2 in Fig. 1, and Fig. 3 is a view of the rear of the recorder installation illustrated in Fig. 1 with the back panel removed.

In the drawings, I denotes a tank having a drain pipe 2: 3 denotes an inner vessel disposed within the tank I and connectible to the source of supply of fluid to be filtered, and 4 denotes an outlet pipe leading from the inner vessel 3 to the inlet 5 of a filtering unit 6. 1 denotes a pressure recorder connected to the outlet 8 of the filtering unit 6 by a pipe 9 in which is intercalated a solenoid-actuated valve I0. II denotes a tank holding a supply of cleaning fluid and connected to the outlet 8 of the filtering unit 6 by a pipe I 2 in which is intercalated a second solenoid-actuated valve I3. I4 denotes a flow controller or module connected to the outlet 8 of the filtering unit 6 by a pipe I5, said module I4 having a discharge orifice I6. I'I denotes a time cycle controller in electrical connection with the solenoids for actuating the valves I0 and I3. I8 denotes the back panel of a casing I9 housing the installation.

In practice, the fluid under test is fed to the inner vessel 3, lls the inner vessel 3 and overflows into the tank I, the overflow that enters the tank running out through the drain pipe 2. Fluid also flows from the inner vessel 3 to the filtering unit 6 and passes through said unit, the head remaining constant, since the depth of fluid in the inner vessel 3 remains constant. The valve I0 is open at this period and the pressure of the fiuid leaving the filtering unit 6 is recorded on a chart by the pressure recorder 1. As the filtering unit 6 gradually becomes choked, the pressure at the outlet 8 drops and the reduced pressure is recorded on the chart of the pressure recorder 1. The quantity of fluid passing through the filter 6 is maintained constant, however, by the flow controller or module I4 which is arranged to open an orifice progressively as the cycle proceeds. At the end of a time interval predetermined by the time controller, the valve I0 leading to the pressure recorder is closed, and, after a brief pause, the valve I3 is opened to admit cleaning fluid. Cleaning fluid flows through the filtering unit 6, cleans said unit, and, entering the inner vessel 3, overflows into the tank I and escapes through the drain pipe 2. The flow controller or module I4 may also be flushed by cleaning fluid at the same time as the filtering unit is cleaned.

After a predetermined time interval the valve I3 that admits cleaning fluid is closed, and, after a brief pause, the valve I0 leading to the pressure recorder 'I is opened, and a new cycle commences.

The length of the line drawn on the chart of the recorder is proportional to the total reduction of pressure resulting during the progressive tions. Although during each cleaning `cycle the cleaning fluid flows back into the ine'r vessel 3, the eiTect on the nal result is negligible since the volumes of the inner vs's'l and f theY pipe 4 leading to the filtering uni't are small; also;

in the interval between thefclosi-ng 'of the valve I3 that admits cleaning fluid and; the re-opening of the valve lil to the pressure recorder 11,

the influx of uid under test clears out almost entirely cleaning uid remaining in the' inner vessel 3. In any case, since the quantity of cleaning fluid remainngfin the pipe 4 connectingthe inner vesselY andthe filtering unit is a constant,l allowance can be made forl-itsrpresence in` the calibration of thepressure recorder T. The

effect of the presence of some cleaningv'fluid afterV each cleaning cycle can be still Afurther reduced by lengthening the period of the filtering cycle.

What is claimed is: e e A i e Y l.V Apparatus forvrmeasuing and recording the ltrability of a fluid lcomprising a tan-k having a dra-in opening, an inner vessel connectible a sourceof supply of liuid to be filtered, said'inner vessel having 4an open rtop and disposed Within said tank, a `filtering unit having an inlet and an outlet, an` outletpipe leading from said inner vessel to the inlet of said lteringunit, a oW controller connected to the outlet of said flltering unit, a pressurerecorder, a pipe connecting the outlet of said filter unit toA said pressure re 2. Apparatus for measuring and recording the filtrability of a uid comprising a flltering unit having inlet and outlet connections through which the fluid to be measured is passed, means forsi-ipplying-` the fluid toy be measured a-t a constarrt Headto" tliinletcfonnec'tion of the filtering unit, a flow controller connected into the outlet connection of the filtering unit and adapted to provide for a constant rate of flow of fluid through the unit, and a pressure recorder connected intothe outlet connection of the filtervi'ig and respsve to changes in the pressuretherein. l,

3L Apparatus 'for measuring and recording the ltrjability of 'a' fluid comprising a filtering unit having inlet and outlet connections through which the fluid; tobe measured is passed, means for supplying thefluid to be measured at a constan't l'ea'd to the inlethconnection of the lter unit, a flow controller connected into the outlet connectionl of the filtering unitv and adapted to \provide for a constant rate of flow of fluid through thewl-ltring unit, a recorder connected into theoutlet connection of the filtering unit, said recorder beingY responsive to changes in the pressure' in saidf outlet,connection and adapted to record an vindicationofthe iiltrability of the fluid, andmeans for controlling the time during which a flteringoperation is conducted.A

Quasi-VAL Ligue1. BOUCHER. NORMAN ANDREW Y FORSTER ROWNTREE.

rtnlsrnuiiironsl CITED The following references lare "of record in th le of this patent: Y

UNITED STATES PATENTS Date Number' y Name 1,333ge14 French Dec. 29, 1931 1,87013211 Adison Y Aug. `9, 1932 1,970,521 v Aug. 14, 1934 2217351 Hughes oct. 15, 1940 2,332,734- Marks 1 Aug. 14, 1945 2,469,293 Davidson May 3, 1949 

